A C. elegans Model for the Study of RAGE-Related Neurodegeneration

The receptor for advanced glycation products (RAGE) is a cell surface, multi-ligand receptor belonging to the immunoglobulin superfamily; this receptor is implicated in a variety of maladies, via inflammatory pathways and induction of oxidative stress. Currently, RAGE is being studied using a limited number of mammalian in vivo, and some complementary in vitro, models. Here, we present a Caenorhabditis elegans model for the study of RAGE-related pathology: a transgenic strain, expressing RAGE in all neurons, was generated and subsequently tested behaviorally, developmentally, and morphologically. In addition to RAGE expression being associated with a significantly shorter lifespan, the following behavioral observations were made when RAGE-expressing worms were compared to the wild type: RAGE-expressing worms showed an impaired dopaminergic system, evaluated by measuring the fluorescent signal of GFP tagging; these worms exhibited decreased locomotion-both general and following ethanol exposure-as measured by counting body bends in adult worms; RAGE expression was also associated with impaired recovery of quiescence and pharyngeal pumping secondary to heat shock, as a significantly smaller fraction of RAGE-expressing worms engaged in these behaviors in the 2 h immediately following the heat shock. Finally, significant developmental differences were also found between the two strains: RAGE expression leads to a significantly smaller fraction of hatched eggs 24 h after laying and also to a significantly slower developmental speed overall. As evidence for the role of RAGE in a variety of neuropathologies accumulates, the use of this novel and expedient model should facilitate the elucidation of relevant underlying mechanisms and also the development of efficient therapeutic strategies.